Carburetor



Jane El, 1935. K. R. BLAKE El AL CARBURETOR Filed Feb. 23, 1952 INVENTORS. Kennefh E. Blake Poberz H. Hill a. Q. 21

ATTORNEY Y B Y Patented Jan. 21, 1936- UNITED STATES PATENT OFFICE z,o2s,sss CABBURETOR F I Application February 23, 1932, Serial N0.594,709

1 Claim.

lean spot encountered in passing from lower to higher speeds and vice versa.

An object of the present invention is to provide a carbureting apparatus wherein one nozzle is effective to supply fuel in proper proportions at all speeds.

A further object of the invention is to provide a carbureting apparatus wherein the supply of fuel is uninterrupted by changes in speed or degree of throttle opening.

Further objects and advantages of the invention will be apparent from the following description, taken in connection with the appended drawing, in which:

.Figure 1 is a diagrammatic sectional view on a horizontal plane, showing an internal combustion engine with the present invention applied thereto;

Figure 2 is an enlarged vertical section of a carburetor and intake manifold embodying the invention; and

Figure 3' is a fragmentary sectional view similar to Figure 2 but showing a modified form of the invention. Y

The invention is. shown as. applieduto a conventional six-cylinder engine Illhaving an intake manifold l2 and a carburetor l4. The carburetor is provided with a float chamber I6 of any suitable construction which supplies fuel to a fuel nozzle IS. The nozzle has its outlet located adjacent the lip of a throttle 20 which controls the passage of air from the air horn 22 to the mixing chamber 24. Positioned above the chamber 24 is an auxiliary throttle '26 which is of the unbalanced type mounted -eccentrically on a shaft 28 and having a spring loaded auxiliary valve 30 controlling'an air oriflce therein. An actuating lever 32 is connected to shaft 28 by means of a coiled spring 34 and lever 32 is connected by a link 36 to bell crank lever." which is fixed to the shaft of throttle 20. and has a vertical arm 40 connected to the usual throttle control rod 42 extending to the driver's position. The throttle control mechanism just described is preferably so adjusted as to prevent throttle 20 from moving to its fully closed position, so that a narrow passageway for air is always open above nozzle I8. Immediately above the lip of throttle 20 and closely adjacent the outlet of nozzle I8 is a port 44 which communicates with a plurality of tubes 46 leading to the intake manifold at spaced points. In the illustrated embodiment, three 19 tubes 46 are shown, and their outlets are opposite the ports 48 leading to the engine cylinders, but this arrangement may be varied if desired.'

In operation, when the engine is rotating at idling speed with the throttles in the positions shown in Figure 2, the throttle will permit the passage of a small volume of air between its upper lipand the wall of the carburetor, and the suction produced by the-Venturi effect of the restrictionwill draw with it fuel from nozzle I8. 20 The resulting mixture does not pass upwardly through mixing chamber 24, however, since the velocity in the mixing chamber is very low. The suction in the intake manifold is relatively high during idling, and is efiective at port 44 to draw the fuel mixture through tubes v415 to the manifold, from which it passes directly to the cylinders to maintain the engine at idling speed If rod 42 is now actuated to open throttle 2o slightly, the subatmospheric pressure in the mixing chamber rises slightly and'at the same time the tension on spring 24 is somewhat relaxed, so

that valve 30 and also throttle 26 may open to a degree determined by the speed of the engine. This results in a portion of the fuel mixture from as nozzle l8 passing through the mixing chamber and intake manifold to the engine, and a lesser amount passing through tubes 46." Further opening of throttle 20 increases this effect,'until when 'the throttle 20 approaches its fully opened position all the fuel mixture flows through the manifold in the usual manner.

In the embodiment shown in Figure 3, the port 44 .is adjacent the lower lip of the main throttle ill, and the upper throttle or air valve 52 is urged toward its, closed position with a constant force by a tension spring 54 connected to an actuating arm 56 fixed to the throttle shaft.

closed until stop '2 contacts with arm I. wherell 2 upon the feed of fuel mixture through tubes 48 will decrease and the carburetor pass quickly to the normal system of fuel feed through the mixing chamber and manifold.

Although the invention-has been described with particular reference to specific embodiments thereof, it is not limited to such embodiments, but may beconsiderably varied within the scope of the following claim.

We claim:

In combination with an internal combustion engine having an intake manifold, a carburetor, a throttle in the carburetor, a fuel nozzle discharging adjacent the lip of the throttle, a plura'lity of conduits leading from adjacent the nozzle to -the manifold, a pressure responsive valve between the carburetor and the manifold, and resilient means influenced by the degree of opening of the throttle for urging said pressure responsive valve toward its closed position.

KENNETH R. BLAKE. ROBERT H. HILL. 

